Medical Minutes
New blood test for detecting early-stage colorectal cancer
A new study has found that a simple blood test can identify circulating tumor cells (CTCs) present in the bloodstream and detect colorectal cancer at an early stage. A preliminary study has found the new blood test has accuracy ranging from 84 to 88 percent.
Most prior studies using CTCs have been able to detect late-stage colorectal cancer. However, this is one of the first clinical studies to show that CTCs can be useful for detecting early, more treatable stages of the cancer. CTCs break away from the primary tumor and travel into the bloodstream where they can form new tumors at distant locations.
“Our study is important because there is still some reticence among patients to use stool-based tests or have an invasive exam like colonoscopy to detect colorectal cancer,” said lead study author Dr. Wen-Sy Tsai, who is an assistant professor, Linkou Chang Gung Memorial Hospital, Taipei, Taiwan. “Our results may point to a solution for people who are reluctant to get an initial screening colonoscopy or are not compliant in returning stool-based test kits that they get from their doctors.”
The study was conducted at Chang Gung Memorial Hospital, Taoyuan, Taiwan. The researchers enrolled 620 people over the age of 20 who were coming to the hospital for routine colonoscopies or had a confirmed colorectal cancer diagnosis. Based on the colonoscopy and biopsy, 438 people were found to have either pre-cancerous growths or early to late-stage colorectal cancers. The remaining study participants had no signs of a pre-cancerous growth or colorectal cancer).
The authors are currently planning to validate the use of CTC testing in the general population in Taiwan and to conduct studies in the U.S. According to the authors, the technology used in this study potentially could be used with other solid tumors, such as breast, lung and prostate cancer.
Mediterranean diet may reduce frailty
A new analysis of published studies is suggesting that following the Mediterranean diet may reduce the risk of frailty in older adults. The findings, which were published in the Journal of the American Geriatrics Society, indicate that a diet emphasizing primarily plant-based foods, such as fruits and vegetables, whole grains, legumes and nuts, may help keep people healthy and independent as they age.
The researchers analyzed evidence from all published studies examining associations between adherence to a Mediterranean diet and development of frailty in older individuals. Their analysis included 5,789 people in four studies in France, Spain, Italy and China.
“People who followed a Mediterranean diet the most were overall less than half as likely to become frail over a nearly four-year period compared with those who followed it the least.” said researcher Kate Walters, PhD, University College London, UK.
The Mediterranean diet may help older individuals maintain muscle strength, activity, weight, and energy levels, according to their findings. Walters said further studies are warranted to elucidate which parts of the Mediterranean diet may be providing the biggest benefits and what may be the optimal approach.
Biodegradable sensor could help doctors monitor serious health conditions
Scientists at the University of Connecticut are reporting they have created a biodegradable pressure sensor that could help doctors monitor chronic lung disease, swelling of the brain, and other medical conditions before dissolving harmlessly in a patient’s body.
The small, flexible sensor is made of medically safe materials already approved by the U.S. Food and Drug Administration (FDA) for use in surgical sutures and medical implants. It is designed to replace existing implantable pressure sensors that have potentially toxic components. Those sensors must be removed after use, subjecting patients to an additional invasive procedure, extending their recovery time, and increasing the risk of infection.
Because the new sensor emits a small electrical charge when pressure is applied against it, the device also could be used to provide electrical stimulation for tissue regeneration, according to the researchers. Other potential applications include monitoring patients with glaucoma, heart disease and bladder cancer.
The prototype sensor consists of a thin polymer film five millimeters long, five millimeters wide, and 200 micrometers thick. The sensor was implanted in the abdomen of a mouse in order to monitor the mouse’s respiratory rate.
“There are many applications for this sensor,” said investigator Thanh Duc Nguyen, who is an assistant professor of mechanical and biomedical engineering in the Institute of Regenerative Engineering at UConn Health.
“Let’s say the sensor is implanted in the brain. We can use biodegradable wires and put the accompanying non-degradable electronics far away from the delicate brain tissue, such as under the skin behind the ear, similar to a cochlear implant. Then it would just require a minor treatment to remove the electronics without worrying about the sensor being in direct contact with soft brain tissue.”
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at medicalminutes@gmail.com.